The best type of chemical for cleaning will depend
on what you want to clean. For example,
water might work in many cases, but it won't
remove oil from your hands. That is when you add
soap. The molecules in soap have
one end which is attracted to the oil molecules
and another end attracted to water
molecules (hydrophobic and hydrophilic
ends, respectively). There are a host of other
cleaning agents to consider though.

This site contains a discussion of the
different types and how they work.

Answer 2:

I like Borax - about 1/4 cup in a load of laundry
to remove odors, along with laundry detergent.

Answer 3:

It depends on what you want to clean, because
different chemicals that need to be cleaned have
different properties. Water is good for
salts or sugars because it dissolves them, but is
not good for oils or many nitrogen-containing
compounds that it can't dissolve.

Bleach breaks down most things that contains
carbon, but you don't want to bleach wooden
furniture or clothes because it will break down
the furniture and clothes just as it will whatever
you're trying to clean off.

Answer 4:

When something needs to be cleaned, it usually
means that there is a material on the surface that
you want to remove. A good way to remove
materials from a surface is to dissolve them in a
liquid and rinse them away, just like you dissolve
salt or sugar in water. In fact, water is a
great liquid for cleaning things, because it
dissolves many materials. A material that
dissolves in water is called water soluble.

However, some materials do not dissolve in
water—they are not water soluble. One
example is oil. Oil and water do not like to mix
with each other, and therefore if you get oil on
your hands, it is hard to wash it off with water
alone.

There are many other materials
that are soluble in oil but not in water. For
example, if you walk on the beach and get tar on
your feet, it will be easier to remove the tar
with oil than with water. So, one way to clean
both water-soluble and oil-soluble materials from
surfaces is to first wash with water, and then
wash with oil. That would be messy though! There
is a better way: soap.

Soap is the common name for a
type of material called a surfactant, also
called a detergent. A surfactant is any material
that has molecules with two sides, a side that
likes water and a side that likes oil.
Surfactants are both water-soluble and oil
soluble. What this means is that you can take
a solution of water and surfactant (one example of
this is liquid dish soap), and it will dissolve
materials that are soluble in water and materials
that are soluble in oil! Common surfactants are
sodium lauryl sulfate and sodium laureth
sulfate which are found in many dish soaps and
shampoos. Look at the ingredients lists of the
soaps around your house and see if you can find
these surfactants!

Answer 5:

The most common household cleaning reagents are
divided into several types. One type is
acidic and includes all kinds of vinegars
and other stronger substances. These can dissolve
minerals that have stuck to surfaces, and some can
break down protein and grease.

Another type is alkaline, which
includes baking soda, lye, and bleach. These can
dissolve protein as well as fats and oils. Both
acidic and alkaline cleaners have electric charges
in water.

A third major type of cleaner is called
surfactants, which we most commonly
encounter as soaps and detergents (dish detergent
is an example). These cleaners typically have
chemical structures that are larger than the
structures of acidic and alkaline substances and
can be good at degreasing as well.

A fourth type of cleaner is what we sometimes
call organic solvents. These are liquids
that are made of carbon and hydrogen atoms
connected together. Organic solvents are
particularly good at dissolving oil-based
substances, including some paints and things such
as tar. However, organic solvents are not as
common as the other three types in household use
because of their potential toxicity to humans;
they should always be used with appropriate
protective equipment (gloves, closed-toed
shoes, masks as necessary) and abundant caution.